= Agenda/Minutes of the VIS Meeting on 2020/4/17 =
2020/4/17 14:00 -

[[https://zoom.us/j/203743987|Zoom Meeting]]

Participants: Takahashi, Sato, Hirata, Tanaka, Shoda, Aso, Fabian, Miyo, Lucia

[[https://paper.dropbox.com/doc/VIS-Commissioning-Task-List--AlK26n6oP8QHU_XUQriwv2PvAg-RKcNXfMFrqOtTAPU48qQf|VIS Commissioning Task List]]

[[https://onedrive.live.com/view.aspx?resid=8E8081C20FE5EC3A!2278&ithint=file,xlsx&authkey=!AMFNtNa-Y6CVp94|Task list towards O4]]

[[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11475|Schedule afetr O3]]

== Progress report ==
=== General ===
(Miyo) I'm gathering information about the hardware part. (e.g. cabling, calibration of sensors and actuators.)
 * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11597|JGW-T2011597]] Calibration factors of LVDTs . 
  * '''Purpose''' : To check the consistency in the klog information.
  * '''Status''' : Please check about Type-A and Type-Bp. ([[https://github.com/gw-vis/kagra-vis/issues/9|Issues list]]) -> __I will make a private meeting with Okutomi-san and Fuji-kun on Saturday to discuss__
  * [[https://github.com/gw-vis/kagra-vis/issues/7|Type-B is OK]]. Thank you fabian! :) 
 * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11573|JGW-D2011573]] Cabling diagram which includes connections among AEL circuits and pin assignment at the feed-through. 
  * '''Purpose''' : To make a consensus about the cabling with AEL and CRYO group for O4. 
  * '''Status''' Need information about the pin assignment for all suspensions -> __Sato-san? and Shoda-san?__

=== Type-A ===
 * Revising the [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5500|Type-A installation procedure]].

=== Type B ===
 * In the context of writing a paper I gathered information about OSEMs and LVDTs and uploaded a document at : [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11612|JGW-T2011612]], which I will be updating.Currently the content is
  * Linear ranges of 24 OSEMs and
  * Sensitivity of the six SRM OSEMS.
 * I gave feedback to Miyo-kun about LVDTs: all the current calibration factors in medm screens are consistent with klog reports. Just as a reminder:
  * The polarity of LVDTs is set in hardware: increase in LVDT output always means upwards motion or positive yaw in the IPs. Therefore, calibration factors in medm screens should always be positive.
  * An exception seems to be BS IP H2 LVDT, whose medm screen I have to check for a minus sign somewhere.
  * The offsets in medm screens correspond to the nominal places of keystones per the 3D-CAD, not the mid-point of the linear range.

=== Type-Bp ===
=== Type-C ===
=== Electronics ===
 * Started the design of LVDT combiner with additional filters.
== Post O3 (4/21~) ==
 * [[https://docs.google.com/spreadsheets/d/1w4q8OvX9E6nkYSgshLYLoZH5yvQXHvGmL1agux8ztx0/edit?usp=sharing|Request]]
 * Papers
  * Type-B: Fabian. Share the contents.
  * Type-A: Lucia. Ask Fujii-kun about his situation.
 * Operation mode at the shutdown of KAGRA
  * Basically safety mode is employed.
  * DC control is turned off for the GAS filters. Monitor the drift. If necessary, require temperature adjustment.
  * DC control is kept for the IPs. Monitor the drift. If necessary, offload by remote.
  * DC control is kept for the BF yaw after the offload. Monitor the drift. If necessary, offload again by remote.

== Towards O3c ==
 * [[https://paper.dropbox.com/doc/Plan-for-the-long-OR-brake--AxxlJFvK1IGJjqrG5nfdHfGXAQ-KqexeqMaCA7DITFGxA5ih|Plan]]: Confusing with the post-O3 task. Should be combined with priority.

== Controls ==
 * For a summary of the current status of inertial damping in Type-B suspensions see the appendix (p14 onwards) in this [[https://1drv.ms/b/s!AoQaV1tdsEcUgc5MtkkqJv5fcCYBrw?e=TXSzu0|presentation]] shown the Commissioning Meeting on the 27th of September 2019.
 * Had the control meeting.

== Safety ==
== Discussion ==
== Travel Plans ==
== Next meeting ==
On 2020/4/24(Fri)